1. Field of the Invention
The present invention relates to a data recording method for recording intermittently or separately data streams of fixed length.
2. Prior Art
FIG. 1 shows a conventional recording format for a data recording system as disclosed in, for example, "Newest Floppy Disc Apparatus and Application Knowhow Thereof", by Shoji Takahashi, CQ Shuppan K.K., June 10, 1984. In the drawing are shown a preamble field 1 for executing bit synchronism, a synchronization pattern field 2 for defining the head position of a data steam, and a data field 3 for recording data.
The operation will next be explained. Since the recording format is formed such as to record the data streams intermittently, the respective data streams are read out from the data field 3 by executing the bit synchronism in the preamble field 1 having a higher sync pattern, such as an all "0" pattern, and then by defining the head position of the data field 3 in the sync pattern field 2. Also, in order to reproduce the head position of the data field 3, the sync pattern fields 2 are written into the recording format in a three-multiple manner.
However, according to the conventional data recording method described above, if an error occurs in the data field and once the bit synchronism is shifted, it becomes impossible to precisely decode the succeeding data. Additionally, since a plurality of sync pattern fields are multiplied in a continuous series, if an error once occurs, it is difficult to define the head position of the data and it is unsuitable, therefore, for the conventional recording format to be applied to a data recording system having a relatively high error rate.